Functions Indoor Unit Operation ON/OFF by Remote controller Sensing the Room Temperature • Room temperature sensor. (Thermistor) Room temperature control • Maintains the room temperature in accordance with the Setting Temp. Starting Current Control • Indoor fan is delayed for 5 seconds at the starting. Time Delay Safety Control •...
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Remote Controller Operation ON/OFF Operation Mode Selection Cooling Operation Mode ( Soft Dry Operation Mode ( Heating Operation Mode ( Auto Operation Mode ( (Cooling (Heating model only) model only) Fan Speed Selection (Low) (Med) (High) Room Temperature Display : High:39°C ↔ LOW:11°C Temperature Setting Down to 18°C Down to 16°C...
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Outdoor Unit Gas side 3-way valve Liquid side 3-way valve MODEL LT-B2421CL/HL, LT-B2461CL/HL LT-B2861HL, LT-B2821HL, LTB3021HL LT-B2861CL, LT-B2821CL, LT-B3021CL 74.5 74.5 –9–...
Wiring Diagram (1) Indoor Unit 1. COOLING ONLY 2. HEAT PUMP –13–...
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(2) Outdoor Unit 2. LT-B2461HL/B2421HL 1. LT-B2461CL/B2861CL/B2421CL B2821CL/B3021CL COMP. Capacitor Capacitor MOTOR MOTOR COMP. CAPACITOR GN/YL P.T.C (OPTION) POWER REVERSING RELAY COIL POWER RELAY GN/YL GN/YL TERMINAL 1 ( N ) 2 ( L ) 3 ( N ) 4 ( L )
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5. LT-B3681CL Outdoor Unit Wiring Diagram R S T N 3Ø, 380-415V POWER SUPPLY THMO 3(N) 4(L) GN/YL OR YL BL BK OR YL BL BK NOTE BL : BLUE RD : RED BK : BLACK WH : WHITE BR : BROWN YL : YELLOW WIRING OF FIELD OR : ORANGE...
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6. LT-B3681HL Outdoor Unit Wiring Diagram C TH T/B1 R S T N 63H2 3Ø, 380-415V POWER SUPPLY 52F2 52F1 BL BK 3(N) 4(L) GN/YL THMO OR YL BL BK OR YL BL BK 20SV BK NOTE BL : BLUE RD : RED BK : BLACK WH : WHITE...
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7. LT-B3621CL/B3661CL Outdoor Unit Wiring Diagram GN/YL POWER SUPPLY THMO BL BK 3(N) 4(L) GN/YL OR YL BL BK OR YL BL BK NOTE BL : BLUE RD : RED BK : BLACK WH : WHITE BR : BROWN YL : YELLOW WIRING OF FIELD OR : ORANGE GN/YL : GREEN/YELLOW...
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8. LT-B3621HL/B3661HL Outdoor Unit Wiring Diagram C TH T/B1 GN/YL 63H2 POWER SUPPLY 52F2 52F1 BL BK 3(N) 4(L) GN/YL THMO OR YL BL BK OR YL BL BK 20SV BK NOTE BL : BLUE RD : RED BK : BLACK WH : WHITE BR : BROWN YL : YELLOW...
Operation Details (1) The function of main control 1. Time Delay Safety Control • 3min... The compressor is ceased for 3minutes to balance the pressure in the refrigeration cycle. (Protection of compressor) • 5sec... Vertical air flow direction control louvers open in 5 seconds to prevent noise between louvers and wind. •...
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6. Heating Mode Operation (Except Cooling Model) The unit will operate according to the setting by the remote controller and the operation diagram is shown as following. Intake Air temp. minimum 3min Setting temp.+3°C (Compressor OFF) Setting temp. (Compressor ON) minimum minimum minimum...
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8. Defrost Control • Defrost operation is controlled by timer and sensing the outdoor piping temperature. • The defrost starts only when the outdoor pipe temperature falls below -6°C after 45 minutes passed from starting of heating operation. • Defrost ends after 9 minutes 30 seconds passed from starting of defrost operation or when the outdoor pipe temperature rises over 12°C even if before 12 minutes.
Installation of Indoor, Outdoor Unit 1. Selection of the best location 1) Indoor unit • There should not be any heat source or steam near the unit. • There should not be any obstacles to prevent the air circulation. Ceiling Ceiling Board Ceiling Board •...
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3) Piping length and the elevation Indoor unit Pipe Size Elevation B(m) * Additional Length A(m) refrigerant MODEL (g/m) Max. Max. GAS LIQUID Rated Rated 24K, 28K, 30K BTU 5/8" 3/8" 36K BTU 3/4" 3/8" Outdoor unit • Rated performance for refrigerant line length of: 5m •...
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2. Ceiling opening dimensions and hanging bolt location • The dimensions of the paper model for installing are 840 (Ceiling opening) the same as those of the ceiling opening dimen- sions. 624(Hanging bolt) 800 Unit size Unit:mm CAUTION • This air-conditioner uses a drain pump. •...
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3. The Indoor Unit Installation Ceiling Keep the length of the bolt Hanging bolt from the bracket to 40mm (W3/8 or M10) Flat washer for M10 Air Conditioner body (W3/8 or M10) (accessory) Ceiling board Ceiling board Spring washer (M10) Flat washer for M10 (accessory) Paper model...
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WIRED REMOTE CONTROL INSTALLATION DISASSEMBLING • Separate the under plate from Remote control box. Front case Lever carefully Remote control • Fix the cord clamps on the wall by the box open box body using a screw ø 3 tapping screws (accessory). driver, etc.
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5. Wiring Connection • Open the control box cover and connect the Remote control cord and Indoor power wires. Remote control cord Indoor Power wires Control Control box cover box cover fitting screw (4 units) [Air inlet side view] Wire taking inlet 1 Phase Terminal Block of Indoor Unit Terminal Block of Outdoor Unit...
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ELECTRICAL WIRING 1. All wiring must comply with LOCAL REGULATIONS. 2. Select a power source that is capable of supplying the current required by the air conditioner. 3. Feed the power source to the unit via a distribution switch board designed for this purpose. 4.
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6. Connecting Pipes to the Indoor Unit • Preparation of Piping Copper Main cause of gas leakage is defect in flaring Slanted Uneven Rough tube 90° work. Carry out correct flaring work in the following procedure. 1) Cut the pipes and the cable. Use the accessory piping kit or the pipes pur- chased locally.
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Piping Connection Liquid side 1. Form the piping according to its routing. Avoid bending and bending back the same piping point more than three times. (This will result in hardening Indoor the pipe.) unit 2. After deforming the piping, align centers of the Outdoor union fitting of the indoor unit and the piping, and Flare connection...
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7. Installation of Decorative Panel The decorative panel has its installation Before installing the decorative panel, direction. always remove the paper template. 1. Temporarily fix two decorative panel fixing screws (hexagon M5 screw) on the unit body. (Tighten by amount 10mm in length.) The fixing screws (hexagon M5 screw) are included the decorative panel box.
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CAUTION Install certainly the decorative panel. Cool air leakage causes sweating. Water drops fall. Good example Bad example Air conditioner unit Air conditioner Cool air leakage unit (no good) Ceiling Ceiling board board Decorative Decorative panel panel Fit the insulator (this part) and be careful for cool air leakage 8.
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HEAT INSULATION 1. Use the heat insulation material for the refriger- ant piping which has an excellent heat-resis- Fastening band (accessory) tance (over 120°C). 2. Precautions in high humidity circumstance: This air conditioner has been tested according to the "KS Standard Conditions with Mist" and con- firmed that there is not any default.
In case of the Outdoor Unit being installed above Seal a small opening position of the Indoor Unit. around the pipings with gum type sealer. 2. Tape the Pipings and Connecting cable from bottom to top. Trap 3. Form the pipings gathered by taping along the exterior wall, and make the trap prevent water from entering into the room.
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2) Connection of power supply 1. Connect the power supply cord to the inde- pendent power supply. • Circuit breaker is required. 2. Operate the unit for fifteen minutes or more. 3) Evaluation of the performance 1. Measure the temperature of the intake and dis- charge air.
3-way Valve 1. Pumping down Liquid side Indoor unit Open Outdoor unit 3-Way valve Gas side Closed 3-Way valve CLOSE CLOSE Purge the air • Procedure (6) Operate the air conditioner in cooling mode (1) Confirm that both liquid side and gas side and stop it when the gaug e indicates valves are set to the open position.
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1) Re-air purging (Re-installation) Liquid side Indoor unit Closed Outdoor unit 2-Way valve Gas side Closed 3-Way valve Gas cylinder OPEN CLOSE • Procedure (6) Disconnect the charge set and the gas (1) Confirm that both the liquid side valve and the cylinder, and set the 2-way and 3-way valves gas side valve are set to the closed position.
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2) Balance refrigerant of the 3-way valve (Gas leakage) Liquid side Indoor unit Outdoor unit 2-Way valve Open Gas side 3-Way valve Open OPEN CLOSE • Procedure (1) Confirm that both the liquid side and gas side (3) Open the valve (Lo side) on the charge set valves are set to the back seat.
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2. Evacuation (All amount of refrigerant leaked) Liquid side Indoor unit Outdoor unit 2-Way valve Open Gas side 3-Way valve Open Vacuum pump OPEN CLOSE • Procedure (1) Connect the vacuum pump to the center hose (3) Close the valve (Lo side) on the charge set, of charge set center hose turn off the vacuum pump, and confirm that the gauge needle does not move (approxima-...
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3. Gas Charging (After Evacuation) Liquid side Indoor unit Open Outdoor unit 2-Way valve Gas side Open 3-Way valve Check valve Charging cylinder OPEN CLOSE • Procedure (1) Connect the charge hose to the charging This is different from previous procedures. cylinder.
Cycle Troubleshooting Guide Trouble analysis 1. Check temperature difference between intake and discharge air and operating current. Temp. difference : approx. 0°C All amount of refrigerant leaked out Current : less than 80% of Check refrigeration cycle rated current Temp. Difference Refrigerant leakege Temp.
Electronic Parts Troubleshooting Guide Possible Trouble 1 : The unit does not operate. Check the FUSE Is the input voltage and the wiring diagram. of transformer AC220V? Is the output voltage Is shorted the Check the main P.C.B of transformer about AC14V? transformer output? pattern.
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Possible Trouble 2 : The indoor fan does not operate. Is it the HOT It is normal operation. START mode? Is IC01M operated Exchange IC01M. normally? Is the each Relay Exchange Relay. any problem? Check the fan motor and connector. (CN-MOTOR) –43–...
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Possible Trouble 3 : Auto Air direction louver does not operate. Is IC01M operated Exchange IC01M. normally? Is the PIN 10 of Check the main P.C.B CN-AC2 DC12V? DC12V pattern. Check the step motor and connector. (CN-AC2, AC1) : Wired remote controller does not operate. Possible Trouble 4 Check the parts of Is the LCD operated...
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Possible Trouble 5 : Ineffective Heating Adjust operation mode. Is it Heating Mode? Does the temperature Adjust set temperature. set all right? Is IC01M operated Change IC01M. normally? Is 4way-valve operated? Check RY-4Way. Check the connector. (CN-OUT, CN-AC1.2) –45–...